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arXiv · 1005.4831

Interplay of thermal and quantum spin fluctuations on the kagome lattice

Dirk Wulferding·Peter Lemmens·Patric Scheib·Jens Roeder·Philippe Mendels·Mark A. de Vries·Shaoyan Chu·Tianheng Han·Young S. Lee
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Abstract

We present a Raman spectroscopic investigation of the Herbertsmithite ZnCu3(OH)6Cl2, the first realization of a Heisenberg s=1/2 antiferromagnet on a perfect kagome lattice. The magnetic excitation spectrum of this compound is dominated by two components, a high temperature quasi elastic signal and a low temperature, broad maximum. The latter has a linear low energy slope and extends to high energy. We have investigated the temperature dependence and symmetry properties of both signals. Our data agree with previous calculations and point to a spin liquid ground state.

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Dirk Wulferding, Peter Lemmens, Patric Scheib, Jens Roeder, Philippe Mendels, Mark A. de Vries, Shaoyan Chu, Tianheng Han, Young S. Lee. 2010-06-10. Interplay of thermal and quantum spin fluctuations on the kagome lattice. https://doi.org/10.1103/physrevb.82.144412

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